NIOSH Publication No. 2005-151:

NIOSH Pocket Guide to Chemical Hazards

September 2005

Acetylene

CAS
74-86-2

C2H2

RTECS
AO9600000
Synonyms & Trade Names

Ethine, Ethyne [Note: A compressed gas used in the welding & cutting of metals.]
DOT ID & Guide
1001 / 116

Exposure
Limits

NIOSH REL: C 2500 ppm (2662 mg/m3)
OSHA PEL: none
IDLH
N.D. See: IDLH INDEX
Conversion
1 ppm = 1.06 mg/m3
Physical Description
Colorless gas with a faint, ethereal odor. [Note: Commercial grade has a garlic-like odor. Shipped under pressure dissolved in acetone.]
MW: 26.0
BP: Sublimes
FRZ: -119°F (Sublimes)
Sol: 2%
VP: 44.2 atm
IP: 11.40 eV
RGasD: 0.91

Fl.P: NA (Gas)
UEL: 100%
LEL: 2.5%

Flammable Gas
Incompatibilities & Reactivities

Zinc; oxygen & other oxidizing agents such as halogens [Note: Forms explosive acetylide compounds with copper, mercury, silver & brasses (containing more than 66% copper).]
Measurement Methods
NIOSH Acetylene Crit. Doc.
See: NMAM or OSHA Methods
Personal Protection & Sanitation
(See protection)
Skin: Frostbite
Eyes: Frostbite
Wash skin: No recommendation
Remove: When wet (flammable)
Change: No recommendation
Provide: Frostbite wash
First Aid
(See procedures)
Eye: Frostbite
Skin: Frostbite
Breathing: Fresh air

Respirator Recommendations
Not available.
Important additional information about respirator selection
Exposure Routes
inhalation, skin and/or eye contact (liquid)
Symptoms
Headache, dizziness; asphyxia; liquid: frostbite
Target Organs
central nervous system, respiratory system
See also: INTRODUCTION   See ICSC CARD: 0089